The present invention relates to the art of brushes, and in particular, a method and apparatus for continuously manufacturing brushes and brush-like material.
In the past there have been three general categories of brush construction, namely, tufted, strip, and twisted in wire type brushes. In tufted brush construction, filament material is gathered into bundles or tufts which are fitted and secured in holes. Such construction is slow requiring the drilling of the holes. The tufts are difficult to handle and frequently clog up machinery and the like. Brushes formed by such construction generally have thick backs to hold the tufts. Bristle distribution is limited by the placement of the tufts on the backing surface.
In strip brush construction, the filament brush material is arranged in strips and clamped. Such construction generally requires a thick mounting for the clamp and other securing means. Strip brush construction further results in brushes which are limited to shapes which are adaptable to being clamped.
Brushes of twisted wire construction generally incorporate filaments within a twisted wire matrix. Such construction does not allow for the fine placement of the of the brush filaments and has found limited use.
My copending patent application soon to issue as U.S. Pat. No. 4,366,592 discloses a method of making brushes by forming a strip embodying a backing sheet with bristles disposed on one face in parallel relation to each other with edges projecting outwardly from one longitudinal edge of the strip. The strip is formed into a predetermined shape and the bristle ends are secured to a base allowing the removal of the backing sheet from the bristles to form a brush-like structure. Such brush-like material is adaptable to a broad range of commercial and industrial appplications. The density of the brush-like material is infinitely variable from a brush face so sparce that the bristles in the brush face can be counted, to a brush face that is so dense it is almost solid bristle. Widely differing length bristles can be accurately distributed within the same brush. Flat even brushes are possible without post trimming. The brush construction disclosed in the earlier application produces brushes that are substantially lighter than conventional brush type material and make more efficient utilization of the area securing the bristle material.
However, the earlier disclosure did not teach a method and apparatus particularly suitable for large scale commercial manufacturing. In particular, the earlier disclosure taught a method of manufacturing brushes which resulted in a brush like structure of circular or eliptical shape. Although the circular shape could be trimmed to an infinite variety of shapes, such trimming resulted in waste of a portion of the circular brush material. The previous teaching of a method for manufacturing brush-like material was not applicable to the felt need of producing a continuous strip of brush-like material which could be more readily incorporated in a variety of industrial applications.